<?php
/**
 * Smarty plugin
 * 
 * @package Smarty
 * @subpackage PluginsFunction
 */

/**
 * Smarty {html_image} function plugin
 *
 * Type: function<br>
 * Name: html_image<br>
 * Date: Feb 24, 2003<br>
 * Purpose: format HTML tags for the image<br>
 * Examples: {html_image file="/images/masthead.gif"}<br>
 * Output: <img src="/images/masthead.gif" width=400 height=23><br>
 * Params:
 * <pre>
 * - file - (required) - file (and path) of image
 * - height - (optional) - image height (default actual height)
 * - width - (optional) - image width (default actual width)
 * - basedir - (optional) - base directory for absolute paths, default is
 * environment variable DOCUMENT_ROOT
 * - path_prefix - prefix for path output (optional, default empty)
 * </pre>
 *
 * @link http://www.smarty.net/manual/en/language.function.html.image.php
 *       {html_image}
 *       (Smarty online manual)
 * @author Monte Ohrt <monte at ohrt dot com>
 * @author credits to Duda <duda@big.hu>
 * @version 1.0
 * @param $params array
 *       	 parameters
 * @param $template Smarty_Internal_Template
 *       	 template object
 * @return string
 * @uses smarty_function_escape_special_chars()
 */
function smarty_function_html_image($params, $template) {
	require_once (SMARTY_PLUGINS_DIR . 'shared.escape_special_chars.php');
	
	$alt = '';
	$file = '';
	$height = '';
	$width = '';
	$extra = '';
	$prefix = '';
	$suffix = '';
	$path_prefix = '';
	$basedir = isset ( $_SERVER ['DOCUMENT_ROOT'] ) ? $_SERVER ['DOCUMENT_ROOT'] : '';
	foreach ( $params as $_key => $_val ) {
		switch ($_key) {
			case 'file' :
			case 'height' :
			case 'width' :
			case 'dpi' :
			case 'path_prefix' :
			case 'basedir' :
				$$_key = $_val;
				break;
			
			case 'alt' :
				if (! is_array ( $_val )) {
					$$_key = smarty_function_escape_special_chars ( $_val );
				} else {
					throw new SmartyException ( "html_image: extra attribute '$_key' cannot be an array", E_USER_NOTICE );
				}
				break;
			
			case 'link' :
			case 'href' :
				$prefix = '<a href="' . $_val . '">';
				$suffix = '</a>';
				break;
			
			default :
				if (! is_array ( $_val )) {
					$extra .= ' ' . $_key . '="' . smarty_function_escape_special_chars ( $_val ) . '"';
				} else {
					throw new SmartyException ( "html_image: extra attribute '$_key' cannot be an array", E_USER_NOTICE );
				}
				break;
		}
	}
	
	if (empty ( $file )) {
		trigger_error ( "html_image: missing 'file' parameter", E_USER_NOTICE );
		return;
	}
	
	if ($file [0] == '/') {
		$_image_path = $basedir . $file;
	} else {
		$_image_path = $file;
	}
	
	// strip file protocol
	if (stripos ( $params ['file'], 'file://' ) === 0) {
		$params ['file'] = substr ( $params ['file'], 7 );
	}
	
	$protocol = strpos ( $params ['file'], '://' );
	if ($protocol !== false) {
		$protocol = strtolower ( substr ( $params ['file'], 0, $protocol ) );
	}
	
	if (isset ( $template->smarty->security_policy )) {
		if ($protocol) {
			// remote resource (or php stream, …)
			if (! $template->smarty->security_policy->isTrustedUri ( $params ['file'] )) {
				return;
			}
		} else {
			// local file
			if (! $template->smarty->security_policy->isTrustedResourceDir ( $params ['file'] )) {
				return;
			}
		}
	}
	
	if (! isset ( $params ['width'] ) || ! isset ( $params ['height'] )) {
		// FIXME: (rodneyrehm) getimagesize() loads the complete file off a
		// remote resource, use custom [jpg,png,gif]header reader!
		if (! $_image_data = @getimagesize ( $_image_path )) {
			if (! file_exists ( $_image_path )) {
				trigger_error ( "html_image: unable to find '$_image_path'", E_USER_NOTICE );
				return;
			} else if (! is_readable ( $_image_path )) {
				trigger_error ( "html_image: unable to read '$_image_path'", E_USER_NOTICE );
				return;
			} else {
				trigger_error ( "html_image: '$_image_path' is not a valid image file", E_USER_NOTICE );
				return;
			}
		}
		
		if (! isset ( $params ['width'] )) {
			$width = $_image_data [0];
		}
		if (! isset ( $params ['height'] )) {
			$height = $_image_data [1];
		}
	}
	
	if (isset ( $params ['dpi'] )) {
		if (strstr ( $_SERVER ['HTTP_USER_AGENT'], 'Mac' )) {
			// FIXME: (rodneyrehm) wrong dpi assumption
			// don't know who thought this up… even if it was true in 1998, it's
			// definitely wrong in 2011.
			$dpi_default = 72;
		} else {
			$dpi_default = 96;
		}
		$_resize = $dpi_default / $params ['dpi'];
		$width = round ( $width * $_resize );
		$height = round ( $height * $_resize );
	}
	
	return $prefix . '<img src="' . $path_prefix . $file . '" alt="' . $alt . '" width="' . $width . '" height="' . $height . '"' . $extra . ' />' . $suffix;
}

?>